Restricted Novel Heat Treatments for Obtaining High Jc in Nb- 46.5 WT.%Ti: II. Prestrain Dependence

  • Peter J. Lee
  • James C. McKinnell
  • David C. Larbalestier
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)

Abstract

In an earlier study, minimal initial heat treatments (3hr/300C) after a large cold work drawing strain (εp=6.37 and 7) were found to be very successful in providing nucleation sites for triple-point α-Ti precipitation during a final full heat treatment (80hr/420C). The minimal heat treatment schedules were repeated and expanded upon in this study but with a cold work pre-strain of only 5. The lower pre-strain reduced the effectiveness of the minimal heat treatment schedules resulting, typically, in a 25% reduction in precipitate volume and in Jc. The Jc and volume % α-Ti values, however, remained remarkably high considering the minimal level of heat treatment and over 2800Amm −2 was achieved at 5T, 4.2K with only one conventional heat treatment (160hr/420C).

Keywords

Heat Treatment Critical Current Density Final Strain Final Heat Treatment Conventional Heat Treatment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    P. J. Lee, J. C. McKinnell, and D. C. Larbalestier, Restricted Novel Heat Treatments for Obtaining High Jc in Nb-46.5wt%Ti, Adv. Cryo. Eng., 36: 287 (1990).CrossRefGoogle Scholar
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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Peter J. Lee
    • 1
  • James C. McKinnell
    • 1
  • David C. Larbalestier
    • 1
  1. 1.Applied Superconductivity CenterUniversity of WI-MadisonMadisonUSA

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